docs: def get_metric(run_id, metric_id):
      """
      Get a specific Sacred metric from the database.
  
      Returns a JSON response or HTTP 404 if not found.
      Issue: https://github.com/chovanecm/sacredboard/issues/58
      """
      data = current_app.config["data"]  # type: DataStorage
      dao = data.get_metrics_dao()
      metric = dao.get(run_id, metric_id)
  
      return Response(render_template(
          "api/metric.js",
          run_id=metric["run_id"],
          metric_id=metric["metric_id"],
          name=metric["name"],
          steps=metric["steps"],
          timestamps=metric["timestamps"],
          values=metric["values"]),
          mimetype="application/json")